The invention is in the field of multiple photoflash lamp arrays.
U.S. Pat. No. 3,935,442 to Hanson describes a flash array of the "FlipFlash" type having a plurality of flash lamps connected to a circuit board having circuitry for sequentially flashing the lamps. A metal-coated plastic reflector unit, shaped to provide individual reflectors for the lamps, is positioned between the lamps and the circuit board, and a metal clip is clipped to the reflector and rests against an electrical ground area of the circuit board so as to electrically ground the reflector and thus increase the stray capacitance of the array's electrical ground to surrounding space, thereby reducing the possibility of accidental flashing of the lamps when electrostatically charged persons or objects touch the array.
The above-referenced Hanson patent application discloses an alternative way of connecting the conductive reflector unit to electrical ground of the circuit board, comprising one or more openings through the rear of the reflector unit aligned with electrical ground pads of the circuit board and shaped to bring a metal coating on the front of the reflector unit against or near to the electrical ground pads. For the purpose of electrically grounding the reflector unit to the circuit board for dissipating any electrostatic charges applied to the array, the connection therebetween need not be a direct contact because electrostatic charges that are likely to cause accidental flashing of the lamps will be about a thousand volts or more (at low energy) and can arc across a short gap between electrical ground of the circuit board and the metal of the reflector unit.
The above-referenced Cote patent application discloses a last-flash indicator arrangement comprising a radiation-actuated switch near the last-to-flash lamp and connected electrically across the input terminals of the array. When the last lamp flashes, the indicator switch changes the resistance across the array's input terminals and actuates a last-flash indicator in the camera.